Source
pub fn update(self: *Adler32, input: []const u8) void {
var s1 = self.adler & 0xffff;
var s2 = (self.adler >> 16) & 0xffff;
if (input.len == 1) {
s1 +%= input[0];
if (s1 >= base) {
s1 -= base;
}
s2 +%= s1;
if (s2 >= base) {
s2 -= base;
}
} else if (input.len < 16) {
for (input) |b| {
s1 +%= b;
s2 +%= s1;
}
if (s1 >= base) {
s1 -= base;
}
s2 %= base;
} else {
const n = nmax / 16; // note: 16 | nmax
var i: usize = 0;
while (i + nmax <= input.len) {
var rounds: usize = 0;
while (rounds < n) : (rounds += 1) {
comptime var j: usize = 0;
inline while (j < 16) : (j += 1) {
s1 +%= input[i + j];
s2 +%= s1;
}
i += 16;
}
s1 %= base;
s2 %= base;
}
if (i < input.len) {
while (i + 16 <= input.len) : (i += 16) {
comptime var j: usize = 0;
inline while (j < 16) : (j += 1) {
s1 +%= input[i + j];
s2 +%= s1;
}
}
while (i < input.len) : (i += 1) {
s1 +%= input[i];
s2 +%= s1;
}
s1 %= base;
s2 %= base;
}
}
self.adler = s1 | (s2 << 16);
}